1. Field of the Invention
The present invention relates to a semiconductor device transmitting and receiving data by wireless communication through an antenna such as an IC card, an RFID tag, an IC tag, an ID tag, a transponder, an IC chip, or an ID chip.
2. Description of the Related Art
A semiconductor device including an antenna and a semiconductor integrated circuit electrically connected to the antenna has been attracted attention as an RFID tag. A manufacturing method of an RFID tag has been proposed, in which a plurality of antennas is provided over a flexible substrate, and a semiconductor integrated circuit is electrically connected to the plurality of antennas (refer to Patent Document 1: Japanese Published Patent Application No. 2005-115646).
A semiconductor device that transmits and receives data by wireless communication through an antenna is interposed between organic resins, and static electricity is easy to be charged in the organic resins. In addition, due to static electricity charged in the semiconductor device, the semiconductor integrated circuit inside the semiconductor device may be broken down and malfunction may be caused by imparting noise to an electric signal.
Therefore, in order to avoid breakdown or interference due to static electricity, a surface of the semiconductor device is covered with a metal plate, whereby a method for preventing breakdown or malfunction in the semiconductor integrated circuit due to static electricity has been implemented.
Although interference due to static electricity is reduced by covering the semiconductor device with the metal plate, transmission and reception of an electromagnetic wave or an electric wave are also obstructed. Then, a communication function of the semiconductor device is degraded. Accordingly, the semiconductor device has a problem in that an electromagnetic wave or an electric wave cannot be transmitted and received through an antenna.